Two months before 9/11/01, an office colleague and I attended a business meeting in the World Trade Center. When the meeting was finished, our hosts asked whether we'd like to go up to the WTC observation deck to look out over lower Manhattan. We checked the time and realized that catching our Acela train back to WDC was already going to be iffy. "We'll check it out it the next time we're back in town."

There never was a next time.

Two months later, on 9/11/01, thirteen years ago this morning, I was on an airplane flying to Pittsburgh. Some colleagues and I took off from Washington National Airport around 0745 and I distinctly remember how the Pentagon filled my window as we banked over it. I've never thrown away the boarding pass stub.

My wife worked in the fitness center of FDIC, across the street to the west of the White House complex. I almost had a panic attack when I saw the White House being evacuated...my mind blanked and I couldn't remember whether it was her day on the early shift or the late shift. It was the latter. She was still at home. Small blessings. We'd been married for all of four months. Had I been on a different plane, she might've been left a widow.

My colleagues and I drove back to WDC in a rental car that we managed to get before they all disappeared once all flight over US airspace were grounded. It took us five hours. We turned on the radio and just listened to the news reports. Nobody said a word.

A week later, my wife and I stood in the dark on a knoll across I-395 across from the Pentagon. We stared at an unfurled flag and a massive hole in the largest building I've ever seen. It was evil made tangible in a way I'd never seen outside of the Holocaust Memorial.

There truly are evil men in this world. It's been one of the great privileges of my life to help fight them. But someday, somewhere, someone else will manage to do something just as horrifying on US soil. Don't live your life in fear, but don't ever think for a minute that we're entirely safe. Evil never truly surrenders...you either destroy it or it falls back to lick it wounds and wait for another day. Just be grateful that there are men and women who've made it their life's work to stand between you and such evil. They have protected you and those you love more times than you'll ever know.